Combining Metal Additive Manufacturing and Casting Technology: High Performance Cooling Channels for Electric Powertrain Components

Abstract

Electric powertrain components require fluid-based thermal management. Al hollow sections integrate in high-pressure die casting (HPDC) promise attractive performance, but require stabilizing fillers affording costly or technically risky removal. Additive manufacturing can facilitate eliminating the filler while further increasing performance via superior material strength, plus geometrical flexibility allowing for internal structuring to enhance heat transfer. Realizing these advantages affords solutions for predicting stability of arbitrary layouts under HPDC conditions. This study compares and validates three approaches employing MAGMASOFT casting simulation individually, and in combination with finite element (FE) simulation. As basis, temperature-dependent mechanical properties for AlSi10Mg alloy processed via laser powder bed fusion are determined between room temperature and 450 °C. Yield strength for the stress relieved material state ranges from 119.63 MPa at RT to 21.90 MPa at 450 °C. Validation of simulation methodologies is done using a test die capable of accommodating tubes of 12 mm outer diameter, with casting experiments performed using a Bühler SC/N 66 HPDC machine. Approaches based on an approximative formula fell short of those combing casting and FE simulation regarding stability limits by a margin of up to 42%. Best match with experimental data is observed for the combined approach.